Solution for the rdpeng#3 week project

cachematrix.R

@@ -1,15 +1,36 @@
-## Put comments here that give an overall description of what your
-## functions do
-
-## Write a short comment describing this function
+# This function creates a special "matrix" object that can cache its inverse.
 
 makeCacheMatrix <- function(x = matrix()) {
+# Although the 'set' function is not required in the description of the task
+#there can be found a phrase in the description of cacheSolve function
+#"(and the matrix has not changed)" implying that the matrix can be changed.
 
+    inv <- NULL
+    set <- function(y) {
+        x <<- y
+        inv <<- NULL
+    }
+    get <- function() x
+    setinverse <- function(inv_2)
+    inv <<- inv_2
+    getinverse <- function()
+    inv
+    list(set = set, get = get, setinverse = setinverse, getinverse = getinverse)
 }
 
-
-## Write a short comment describing this function
+# This function computes the inverse of the special "matrix" returned by
+#makeCacheMatrix above.
+# If the inverse has already been calculated (and the matrix has not changed),
+#then the cachesolve should retrieve the inverse from the cache
 
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+    inv <- x$getinverse()
+    if(!is.null(inv)) {
+        message("getting cached data")
+        return(inv)
+    }
+    data <- x$get()
+    inv <- solve(data, ...)
+    x$setinverse(inv)
+    inv
 }